SF Super Heroes

One scientist and his monster, Frankenstein and the Monster, initiated the transition from Gothic fiction to science fiction.

One extraterrestrial superman, called Superman, initiated the transition from science fiction to the new composite genre of super heroes, mainly associated with one visual medium, comics, but currently transferring to another, cinema.

Some subsequent sf characters are effectively super heroes although not labelled as such:

the mentalists in James Blish's "Citadel of Thought";
Julian May's Diamond Mask and Jack the Bodiless;
Larry Niven's Gil "the Arm" Hamilton and the protectors;
Poul Anderson's Un-Men and the Sensitive Man.

Like many of Anderson's characters, the Un-men and the Sensitive Man are potential series characters but their author had other things to write.